Rotatable tool for sinking wells in the ground



Nov. 3, 1959 A, P, JOURDW 2,911,194

ROTATABLE TOOL FOR SINKING WELLS -IN THE GROUND Filed March 6, 1957 Uni ed States patgnto P ROTATABLE TOOL FOR SINKING WELLS IN THE GROUND Andr Paul Jourdain, Embourg-lez-Liege, Belgium, as-

signor to Compagnie Internationale des Pieux Armes Frankignoul, Societe Anouyme, Liege, Belgium Application March 6,1957, Serial No. 644,334

Claims priority, application France March 12, 1956 4 Claims. (Cl. 255-65) The invention relates to a rotatable tool for sinking wells in the ground, the said tool comprising articulated blades arranged at its bottom end, these blades being open for digging the ground over a relatively large diameter, while they are closed in order to lift the drilling debris and to permit their removal from the wells as they are being produced. It Will be understood that for the tool to be able to dig the ground effectively and to act as a drill, the open blades must have a sufiicient angle of the cutting edge, each blade then occupying a position such that, seen in any plane perpendicular to the axis of rotation of the tool the body-f the blade approaches the tool axis from its frontal edge, that is to say the front edge with respect to the direction of rotation of the tool. The arrangement must at the same time be such that in the working position, a large entry for the earth in the radial direction is formed between the successive blades. The blades act as a grab when they are closed.

These conditions can be satisfied to a certain degree by blades having the general form of a skew surface, but this form does not permit complete closure of the grab, since openings always exist between the adjacent blades.

, The construction of blades having such a special shape is however complicated and costly. Furthermore, a tool provided with blades of this type does not permit a perfect removal of the debris resulting from the drilling and cannot be used practically when working in soft or watery soils.

One object of the invention is to provide a tool which perfectly satisfies the aforementioned conditions while permitting complete closure of the blades. Another object of the invention is to obtain this result by using blades which are of regular shape and the manufacture of which is simple and relatively inexpensive.

To this end, the invention provides for the blades each to be articulated on the tool body by means of a hinge which is at least approximately perpendicular to a radial plane of the rotatable tool situated in an area close to the frontal edge of the blade. The hinge is advantageously situated in this area in such manner as to reduce the forces which act on the hinge under the effect of reactions to which the blade is subjected during the drilling, but the hinge may be disposed at a different point on the periphery of the blade, provided that it is perpen' dicular to the said radial plane. According to the invention, the blade may therefore be of regular shape, particularly that of a sector of a surface of revolution which is of ogival form.

The frontal or leading edge is generally provided with a cutter projecting forwardly and outwardly. According to the invention, this cutter is advantageously formed in such manner that its internal face is extended slightly into the extension of the external face of the blade, so as to be applied to the external face of the adjacent blade when the grab is closed. In order better to ensure tightness, the invention provides for an elastic joint being mounted in the rear edge of each blade.

Other features and advantages of the invention will be apparent from the description of one construction given by way of example, this description following and being considered by reference to the accompanying diagrammatic drawing, in which:

Fig. 1 is a view, partly in vertical section, of a tool according to the invention.

Fig. 2 is a diagrammatic plan view of the blades to a larger scale, taken from inside the tool, and

Fig. 3 is a fragmentary View to a larger scale of contiguous parts of two adjacent blades. v

The body of the tool can be of any desired type capable of carrying out a rotational movement about its axis and provided with means for controlling the opening and closing of the blades.

In the example illustrated, 1 represents the tool body, to which a rotational movement can be imparted by a rod 2, which can for example be hollow and which extends upwardly, the said rod being set in rotation by any suitable means. The movements for opening and closing the blades can be controlled by any suitable means, for

' example by means of an axially movable member 3 which slides in a partition 4 of the body 1 and which controls the blades by a mechanism which will be hereinafter described. The said means can for example be formed by a pulley block mounted in the body 1 and the movable equipment of which, carrying the movable pulleys of the pulley block, is fast with the member 3, whereas the fixed pulleys are mounted above said movable equipment carried by the body 1. The pulley block cable 5 extends upwardly through the rod 2, while its other end is fixed to the body 1. 5

The body 1 terminates in a sleeve 6, the blades 7 being articulated on the edge thereof by means of hinges 8. In the example illustrated, three blades are provided, but this number can obviously vary. Moreover, the shape thereof can be modified according to the particular requirements of the ground. They are easy to replace, be-

cause it is suflicient to remove the pin of the hinge in order to permit their replacement or else the blades can be bolted to the arms 9.

Fig. 1 shows diagrammatically the working position 7a and the fully open position 7b for emptying purposes, the chain-dotted line at the right of the figure representing the corresponding positions of another blade which would have been turned so as to bring it into the plane of the drawing.

Each blade is extended upwardly by an inwardly curved arm 9, the free end of which is pivoted at 10 to a rod or link 11. The links 11 are pivoted at 12 to extensions 13 of a member 14 which is connected to the part 3 by means of a screw 15 so that it participates in the axial movements of the part 3, which movements thus produce the opening and closing movements of the blade. When a pulley block system such as that mentioned above is used, the lowering of the part 3 is produced by the weight of the movable equipment of this pulley block system, the cable 5 being relaxed, while the lifting of the part 3 for closing the blades can be produced by an upward pulling movement on the said cable, this producing the upward movement of the movable equipment of the pulley block, including part 3, against the action of the weight of the remaining part of the tool, which is transmitted to the links 11. It would of course be possible to use any other mechanism for controlling the blades.

As shown in Fig. 2, the hinge is arranged at a point corresponding to a radial plane R disposed in the area close to the frontal edge of the blade, which is provided with a projecting cutter 16. The hinge 8 is perpendicular to this plane R so that during the pivotal movement all the points of the blade will be displaced parallel to this plane. In the position 7a, the blade will thus be disposed approximately as indicated in chain-dotted lines (in Fig. 2), the blade, seen transversely to the axis of rotation of the tool. being in a general position inclined towards the rear and towards the axis of the tool so as to give a sufiicient angle of the cutting edge of the cutter 16 and to form between the blades large openings A for the entry of the earth into the grab formed by the blades. The plane R should be disposed in the zone situated towards the front with respect to the mean radial plane Rm of the blade and-preferably close to the front edge,

or coinciding with the front edge.

The hinge may however be arranged at any point of the periphery of the blade, provided that it is at least substantially perpendicular to a plane R as defined as above, or in other words, the hinge 8 illustrated could be located more towards the rear on the edge of the blade, provided that it can be arranged in a position parallel to that of the hinge illustrated. It is nevertheless advanta- 'geous to arrange it close to the frontal edge in order to reduce the forces which act on the hinge under the effect of the reactions to which the blade is subjected during the sinking operation.

In order to assist the descent of the tool in the ground during the sinking operation, helical ribs 17 can be provided on the external faces on the blades. These ribs extend for a certain distance, starting from the cutters 16, and the maximum height thereof corresponds substantially to that of the cutters.

It will be seen that the blades can be of a very simple shape, particularly that of sectors of a surface of revolution as illustrated.

When the tool is withdrawn for emptying purposes, the traction exerted on the cable will first of all produce an upward movement of member 3, eg through the above mentioned pulley block, so as to close tightly the blades against each other by means of arm 9 and members 11 and 13, which are displaced under the control of member 3, the weight of the remaining part of the tool supplying the necessary reaction. Further traction on the cable will produce lifting of the complete tool with the grab tightly enclosing the earth. When working in compact or coherent ground, it would be possible for the grab not to be completely closed, but the earth would however not fall out and the grab would even take up a larger volume than its normal capacity.

However, in liquid-bearing ground, it is advantageous to improve the tightness of the grab, although it would be completely closed in this case. For this purpose, the invention provides a construction such as that illustrated in Fig. 3. The cutter 16 is welded to the outside of the blade and has the same curvature as the latter. It is extended slightly towards the front of the blade so as to form an effective baffle with the adjacent blade when the grab is closed. In addition, a groove can be formed in the thickness of the rear edge of the blade in order to serve as a seating for a joint 18 consisting of rubber or similar material. In the position occupied during the sinking operation, which position is shown in chain-dotted lines, the joint 18 will not be subjected to any friction with the ground, because it is situated at the rear of the blade.

The invention also provides a construction which obviates the use of any mechanical member in the internal space defined by the blades so as to obviate any adhesion of the earth and to permit complete and convenient emptying. Each blade has fixed thereto an arm 9 which extends upwardly and inwardly. The control of this arm is effected from above, that is to say, from outside the blade, so that the members 11, 13 and 15 are moved inside the sleeve 6 without extending into the actual cavity 4 of the grab formed by the blades. This sleeve at the same time forms an effective protection for the said members.

It is obvious that the invention is not limited to the constructional form which has been described and illus' trated, which may undergo various modifications Without departing from the spirit of the invention.

It will also be obvious that where the hinge, such as 8, should be at least substantially perpendicular to a radial plane of the tool disposed in a zone close to the frontal edge of the blade, such hinge can possibly have a certain inclination with respect to said plane.

What I claim is:

1. A tool rotatable about its axis for sinking wells in the ground comprising a tool body, a plurality of blades extending beyond the tool body and arranged one beside the other along the periphery of the lower end portion of the tool body, hinges, each blade having its upper end portion connected to the lower end portion of the tool body by means of one of said hinges which defines a pivoting axis therefor, which pivoting axis is substantially perpendicular to a radial plane of the tool body located in the forward half of the corresponding blade, and means for imparting pivotal movement to the blades each about its pivoting axis for opening and closing the blades.

2. A tool as claimed in claim 1, in which a cutter having an outwardly and forwardly inclined front edge is positioned on the outer face of each blade along and projecting forwardly beyond the frontal edge thereof, the inner face of the projecting portion of said cutter being tangential to the outer face of the adjacent blade in the closed position of the blades.

3. A rotatable tool for sinking wells in the ground, comprising a tool body, a plurality of blades extending beyond the tool body and each connected thereto by means of a hinge connecting the upper end portion of the blade to the lower end portion of the tool body, said hinge defining a pivoting axis being at least substantially perpendicular to a radial plane of the tool located in the forward half of the corresponding blade, means for opening and closing the blade, the blades being sectors of a hollow pointed body with an open bottom and with its apex at the lower end of the blades, a groove being provided in the rear edge of each blade, and a packing joint fitted in each groove for inter-blade engagement.

4. A tool rotatable about its axis for sinking wells in the ground comprising a tool body, a plurality of blades extending beyond the tool body and arranged one beside the other along the periphery of the lower end portion of the tool body, hinges, each blade having its upper end portion connected to the lower end portion of the tool body by means of one of said hinges which defines a pivoting axis therefor, which pivoting axis is substantially perpendicular to a radial plane of the tool body located in the forward half of the corresponding blade, and means for imparting pivotal movement to the blades each about its pivoting axis for opening and closing the blades, the blades being sectors of a hollow pointed body with an open bottom and with its apex at the lower end of the blades.

References Cited in the file of this patent UNITED STATES PATENTS 838,614 Frank Dec. 18, 1906 1,499,938 Leedorn July 1, 1924 1,986,095 Allard Jan. 1, 1935 2,177,196 Williams Oct. 24, 1939 FOREIGN PATENTS 354,914 Italy Dec. 14, 1937 886,582 Germany Aug. 17, 1953 

